StoRHm: A Protocol Adapter for mapping SOAP-based Web Services to RESTful HTTP Format

Abstract

Two of the most popular approaches to Web Services' implementation are SOAP-based Web Services, which are based on an XML messaging protocol and RESTful HTTP Web Services, which use HTTP in line with Representational State Transfer (REST) principles. RESTful HTTP Web services adhere closely to REST principles and therefore avail of existing sophisticated features of Web infrastructure. SOAP on the other hand, uses HTTP purely as a transport for its messages. This is known as 'SOAP tunnelling' and is against REST principles because it disables Web intermediaries, as they are unable to inspect the SOAP message. The research documented in this thesis proposes a protocol adapter named StoRHm (SOAP to RESTful HTTP mapping) that, within certain constraints, addresses SOAP tunnelling by seamlessly transforming opaque SOAP messages into visible RESTful HTTP format. The previously opaque messages are now visible to Web intermediaries, thereby enabling advanced Web features such as caching. The adapter described in this research enables SOAP clients to interact seamlessly with back-end RESTful Web services. Thus, StoRHm is also a technology migration enabler i.e. an enterprise can migrate from SOAP-based Web Services to RESTful HTTP Web services, in a gradual fashion, by adopting the adapter. StoRHm proposes to leverage the Semantic Web to automate the mapping element of its solution.